[73.07] Interactions between Radio Galaxies and their Environments

A.M. Koekemoer (NASA/GSFC)

The immediate environment of radio galaxies plays an
important role in determining their overall properties,
specifically in terms of confinement and long-term evolution
of the sources. The extent of interactions between radio
galaxies and the ambient medium can be traced by examining
the properties of the radio synchrotron lobes and jets,
together with the energetics and ionization of optical
line-emitting gas that is often associated with these
sources. Other effects, for example star formation induced
by the passage of the radio jets, have also been inferred in
a number of objects. Here I present results from a program
of detailed emission-line imaging and spectrophotometry of
radio galaxies, making use of spatially resolved line ratios
and gas kinematics to determine the physical properties of
the gas and investigate its energetic relationship with the
radio plasma. The observations are compared with results
from ionization models using the codes MAPPINGS-II and
CLOUDY, as well as hydrodynamic models of interactions
between the radio jets / lobes and ambient gas. The
implications are discussed in the context of the effects of
the environment on the evolution of radio sources, together
with the reciprocal impact of radio sources upon their
environments.